This invention relates generally to exercise equipment. Specifically, the invention relates to an exercise device which is propelled by the user. More specifically, the invention relates to a foot powered exercise device such as a bicycle or the like. Most specifically, the invention relates to a self-propelled exercise device in which the user""s foot travels in a generally elliptical path.
Elliptical exercise devices provide a low-impact, aerobic form of exercise in which a user""s feet move along a generally elliptical path of travel which simulates a natural running and stepping motion. The action of such devices is superior to that achieved by stair steppers, stationary bicycles or ski machines. In general, such elliptical exercise devices have heretofore been configured as stationary devices. In many instances, users prefer to engage in a mobile form of exercise such as running, bicycling, and the like. Heretofore available, foot powered, mobile exercise equipment has not been able to provide a suitable, elliptical path of foot travel. Within the context of the present disclosure it is to be understood that an xe2x80x9cellipticalxe2x80x9d path of foot travel comprises a generally elongated, closed, curved path of travel which encompasses mathematically perfect ellipses, as well as more irregular shapes such as ovals, flattened ellipses and the like. In one specific elliptical path of travel, as achieved by specific embodiments of the present invention, a user""s foot travels along a path such that when moving forward, the heel portion of a user""s foot initially rises at a faster rate than the toe portion, and when the user""s foot is moving rearward, the heel portion initially falls at a faster rate than does the toe portion. All of such elliptical paths of travel have been found to provide a comfortable and natural action which is conducive to continued and productive exercise.
As will be explained hereinbelow, the present invention provides a user powered exercise device, such as a bicycle, which operates to provide an elliptical path of foot travel. Furthermore, the mechanical configuration of the present invention may be readily adapted to variously configured production models of bicycles; therefore, the present invention may be readily manufactured with minimal tooling commitments. These and other advantages of the present invention will be readily apparent from the drawings, discussion and description which follow.
There is disclosed herein a self-propelled exercise device which comprises a frame having a drive wheel rotatably supported thereupon, and a first pivot axis defined upon the frame. The device includes a first and second foot link, each of which has a foot receiving portion defined thereupon, and a coupler assembly which is in mechanical communication with a first pivot axis and with a first end of each of said first and second foot links. The coupler assembly is operative to direct the first ends of the foot links in an arcuate path of travel. The apparatus also includes a foot link guide which is supported by the frame. The foot link guide is operable to engage a second end of each of the foot links and to direct the second ends along a reciprocating path of travel. The apparatus further includes a power transfer linkage which is in mechanical communication with the coupler assembly and with the drive wheel. When the second end of one of the foot links travels in a reciprocal path, and the first end of that foot link travels in an arcuate path, a user""s foot supported thereupon travels in a generally elliptical path of travel and the power transfer linkage transfers power from said coupler assembly to the drive wheel so as to supply propulsive power thereto.
In specific embodiments, the foot link guide may comprise one or more tracks which engage second ends of the foot links, or the guide may comprise a pair of swing arms pivotally supported on the frame so that each arm engages a second end of a respective foot link and directs it in the reciprocating path of travel. The coupler assembly may comprise a pair of crank arms which are pivotally supported at the first pivot axis.
In another embodiment, the coupler assembly may include a first and a second drive link, and a first and second coupling member, each of which is in mechanical communication with the first end of a respective one of the drive links and with the first pivot axis. In this embodiment, each coupling member is operative to direct the first end of its respective drive link in an arcuate path of travel. In this embodiment, there is also included a drive link guide which is operable to engage a second end of a respective one of the drive links and to direct that second end along a reciprocal path of travel. In this embodiment, the first end of each foot link is coupled to a respective one of the first and second drive links so that the drive links will direct those first ends in the arcuate path of travel. In some embodiments, the device of the present invention is configured as a bicycle, and in that regard may include additional features such as a seat, handlebars, and a geared transmission.
Also disclosed is a bicycle frame which is specifically configured for use in the present invention. The frame includes an integral track for guiding the foot links in a reciprocal path.